She helps him become popular by: A) helping him score touchdowns, B) getting him good grades, C) killing his science teacher with ice cream, D) drowning a meddling guidance counselor in battery acid.
Once Alex becomes “cool” he dresses like a 50’s style delinquent and rides a motorcycle. He covers up Mary Lou’s murders by burying the bodies in the football field (and has a dream that they come back as zombies to kill him), but when Mary Lou kills the rival quarterback with a spiked football, he breaks up with her. She appears to him in a Sex Education movie called “Social Disease” and vows to get back at him. Mary Lou (who has Freddy style nails) rips out his best friend’s heart and frames Alex for the crime. He escapes the police and must save his new girlfriend Sara from the spiteful Mary Lou. At the prom, Mary Lou sends Alex straight to Hell, and Sara follows. Hell is just high school (get it?) but with red lights. Mary Lou’s victims attack Sara and she burns them with a flame thrower. She’s also attacked by a killer juke box that shoots spiked records! At the Zombie Prom, Mary Lou tries to crown Alex king, but Sara blows her up! They escape Hell together, but end up in the 50’s!
Then, appropriately, there’s a rap song over the end credits.
This nutty movie also has Evil Dead style camerawork, and MASH style morning announcements, and there’s more intentional humor than in Part 2 (some of which is pretty damn funny). It also has some choice death scenes and has a goofy charm. Conlan is good and reminded me of Zach Galligan. His best line is: “I’m popular, and all I had to do was dig a few holes and bop a ghost!” Ray Sager again produced.